These babies work like a dream. We bought this little, under-$5000 used Prius (no car payments, yay!), but whoever owned it before used it as his or her ashtray. Blech. We had the car professionally detailed, the whole ozone thing, and numerous air fresheners, but it just never got the smell out. This is the MOST EFFECTIVE product we've found for taking the smoke smell out of the Prius. I put two in the car, both on the back of the front seats. The smoke smell isn't 100% gone, but when I do notice it, it is very very faint. This product does the best job of anything we've found.
PURGGO Car Air Freshener - Auto Odor Eliminator - 100% Activated Bamboo Charcoal Air Purifier, Ionizer - Absorb and Remove Smoke Smell - Fragrance-Free Deodorizer - Lasts 365+ Days [Classic Beige]

Wife wrote this: We have definitely liked these! I just ordered 3 more car sized ones and 3 pairs of the smaller ones. I figured the car sized ones would be good in a single smallish room, much like a car which has its doors opened a bunch.
The large one in the car has removed a lot of odors since it was installed four months ago. . . Let's face it, sometimes humans create noxious fumes and everyone is stuck in the car for hours with them. The car no longer stinks! Yea! We have not put it out in the sun. The instructions say to put it out in direct sunlight for an hour a month. It has been continuously hanging on the back of a headrest for 4 months. The car gets so hot when parked that, perhaps, it is rejuvenating itself. Maybe sun through the windows is enough.
We traveled and used two of the smaller ones to remove odors from our closets and suitcases when we were unable to do laundry for two weeks. Very successful! Then, we came home to what smelled like a mouse had died somewhere in our Great Room. We tried to localize the smell but still cannot figure out from where the handful of flies are hatching. We never have had more than a handful of flies in the house all year. Lately, however, there are around 3 or more buzzing around or lying dead someplace. The flies make us pretty sure that something died somewhere, but where?????. The AC is on so the air is moving and we cannot really localize the smell. I suddenly remembered the two small odor eliminators I had put into a thick sealed plastic bag. I brought them out yesterday and hung them up in the section of the room where the smell is strongest, near stuffed cabinets, a desk and full bookshelves. This morning the smell was much less. So I just ordered more of these for other trouble spots in the house and cars. We really like the fact there is no synthetic perfume left wafting around to cause us to sneeze.

This thing works. I like my car to smell fresh, not perfumey. I hung this on my seat. It looks nice, kind of non-descript and just blends in. I hardly notice that it's there. So it hung there for a while and I thought "well, I guess it's working" but my car was already clean and smelling great, so I wasn't sure. The day before thanksgiving, I picked up a cooked turkey, ham, brisket, and beans. Woooo, smelled like a barbecue restaurant at lunchtime in my car. Smelled good at the time, but two hours later, I wanted it gone. The next morning, I got in my car and it was gone! My car smelled fresh without a hint of smoked meat. Amazing!!

This item has been inside my car for 2 weeks and has corrected zero of the odor problem. It still smells musty and stale. I put it out in the sun thinking maybe the product needed revamping. (It is a new product) but no change. I do not recommend this product.

This thing does nothing. If you carry food in your car on your way from work or wherever and get in the next day, you can still smell the food.

This was supposed to replace the need for an air freshners but I find myself having to go back to them.

Don't spend your hard earned money on this crap. It's a waste and a sick joke. The manufacturers are probably sitting in their office laughing at all their customers.